The present invention relates to a device for extracting auxiliary power from a power source, and more particularly to a device for extracting auxiliary power from a power source installed on or associated with an implement, and supplying the auxiliary power to an auxiliary tool associated with the implement. In a typical preferred embodiment, the invention is advantageously employed in the context of an auxiliary tool, e.g., in the form of a rotary trimmer, edger or the like associated with another power implement, such as a lawn mower. The power is preferably extracted from a driven member of the implement, which maximizes retrofitability.
There have been many prior attempts to provide devices for extracting auxiliary power from a power source, including in the context of supplying auxiliary power to an auxiliary tool such as a rotary trimmer. One such attempt is illustrated in Qualls U.S. Pat. No. 4,653,254, which relates to a hand-held string trimmer that is powered by the engine on a push lawnmower, by attaching a collar member 28 to the top end of shaft 16 of the motor power source 12 of the lawnmower and connecting the collar and trimmer with a flexible drive shaft. Attachment is by means of a detent fit between circumferential shoulder 36 of a first cylindrical locking member 32 and recess 44 extending circumferentially about the interior of coupling member 42. Similar is Beaver U.S. Pat. No. 4,242,855, which also discloses the option of additionally driving a sprayer pump from a pulley attached to the top end of the motor drive shaft.
Another attempt is illustrated in Owens U.S. Pat. No. 4,642,976, which is directed to an attachment for edging or trimming grass that is designed to be attached to a lawnmower or a vehicle/riding lawnmower by a bracket, in such a way that the edge/trimmer head can be raised, lowered and rotated with respect to the bracket. At the end of the head opposite its cutting members, there is a quick disconnect joint which allows either an electric motor to be mounted and energized by electrical power available aboard the mower, or alternatively allows a cable drive to be mounted which drives the head from a friction drive mechanism taking power from the mower engine shaft.
Borunda U.S. Pat. No. 3,604,208 discloses an alternative arrangement for powering an edger from the engine of a push lawnmower. A bevel gear mounted on the vertical drive shaft of the engine allows selective engagement of a mating bevel gear to drive the trimmer. The mower blade is also selectively engageable.
U.S. Pat. No. 4,559,768 to Dunn describes a device such as a push lawnmower that has a gasoline-powered engine/generator mounted on the mower deck. This generator can be used to power an electrically-driven mower blade, or alternatively an auxiliary device, such as a trimmer.
Several other devices have been proposed in which an auxiliary pulley is secured to the drive mechanism of a mower, where this pulley is employed to drive an auxiliary trimmer. On such device is shown in Ould U.S. Pat. No. 4,715,169, which has a trimmer mounted on the mower deck and a flexible shaft driving the trimmer from a secondary pulley that is belt-driven from the auxiliary pulley attached to the top end of the motor drive shaft. Bares U.S. Pat. No. 6,892,518 discloses an edge trimmer assembly that is mountable on the deck of a lawnmower, such as a riding lawnmower having a mower deck comprising a plurality of cutting blades. In one embodiment, the trimmer is driven by an auxiliary v-belt surrounding an auxiliary pulley attached to one of the pulleys that is part of the mower deck and is used to drive one of the blades.
In addition to the Bares patent, two other patent documents (Hatfield U.S. Pat. No. 7,219,488 and Heighton US 2004/0237491) are illustrative of today's state-of-the-art regarding the professional/commercial lawnmowing trade, in which the use of an auxiliary trimmer device is found to be very desirable in order to increase efficiency and lower the labor cost of caring for extensive areas of lawn, e.g., cemeteries, office buildings, parks, public buildings, schools, etc. Most typically, the so-called “Zero-Turn-Radius” (ZTR) riding lawnmowers have been found to be most efficient and are consequently used for the most significant part of this trade, i.e., in which there is usually a company-owned fleet comprised of a plurality of mowing machines that, over time, evolve (due to addition and/or replacement) to include machines of multiple different configurations.
In most of these documents, the intent is to provide an auxiliary device, such as a trimmer, that is retrofittable to existing commercial lawnmower models. However, in each instance, the respective devices are practically limited to a very small number of commercial products, and/or the retrofit requires substantial and not quickly reversible changes to existing commercial machines, e.g., firmly attaching auxiliary drive parts to a shaft that is either an engine drive shaft or part of a pulley for powering a mower cutting blade. Furthermore, each of the many commercially available Zero-Turn mowers is configured differently (as is the case for nearly all other designs for lawnmowers, large and small), such that there is virtually no practical possibility to utilize any of these devices interchangeably from one machine to another. Although the use of magnets has been known for centuries to temporarily attach items together, including temporarily holding a flashlight, even on a lawn mower (See US 2016/0116145A12), magnets are not deemed suitable for attaching parts of machinery together, particularly driving/driven pairs of parts and/or moving parts that are subject to forces and/or vibration, as in the context of, for example, a power lawn mower.
The same is true with respect to the mechanism for mounting an auxiliary trimmer onto the body or mower deck of these commercially used mowers. Apart from having to detach and re-attach the specially configured bracket mechanisms when attempting to switch between different mower models, in many cases the brackets will not readily fit onto differently configured mower decks. In addition, there are mutually-contradictory demands, on the one hand, to be able to easily move an auxiliary trimmer into the needed orientation vis-à-vis the mower deck, and on the other hand, to simultaneously protect the trimmer from damage and/or detachment upon inadvertently striking an obstacle with the trimmer.
For these reasons, the market does not currently offer a practical, universally usable and retrofittable auxiliary trimmer attachment, whereby those responsible for maintaining large tracts of lawn have not been able to make full use of the economically advantageous option of simultaneously mowing and trimming utilizing a single mower unit, especially in the case of commercial fleets of mowing machines that comprise plural machines of differing configurations. There is a current demand for a product that is capable of fulfilling this need.